The was an amphibious

medium tank A medium tank is a classification of tanks, particularly prevalent during World War II which represented a compromise between the mobility oriented light tanks and the armour and armament oriented heavy tanks. A medium tank's classification ...

developed by the

Imperial Japanese Navy The Imperial Japanese Navy (IJN; Kyūjitai: Shinjitai: ' 'Navy of the Greater Japanese Empire', or ''Nippon Kaigun'', 'Japanese Navy') was the navy of the Empire of Japan from 1868 to 1945, when it was dissolved following Japan's surrender ...

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the World War II by country, vast majority of the world's countries—including all of the great power ...

. The Type 3 Ka-Chi was based on an extensively modified

Imperial Japanese Army The was the official ground-based armed force of the Empire of Japan from 1868 to 1945. It was controlled by the Imperial Japanese Army General Staff Office and the Ministry of the Army, both of which were nominally subordinate to the Emperor ...

Type 1 Chi-He medium tank (it had 2 more road-wheels and two more return rollers on each side) and was a larger and more capable version of the earlier Type 2 Ka-Mi amphibious tank.

History and development

The success of the Type 2 Ka-Mi design pleased the planners in the

Imperial Japanese Navy General Staff The was the highest organ within the Imperial Japanese Navy. In charge of planning and operations, it was headed by an Admiral headquartered in Tokyo. History Created in 1893, the Navy General Staff took over operational (as opposed to adminis ...

, and it was determined that a larger version with stronger armor and armament would be useful in future amphibious warfare operations. The Type 3 Ka-Chi prototype was completed in late 1943 and the first units entered service that same year. However, only 12 to 19 Type 3 Ka-Chi's were built from 1943 to 1945. The main priorities of the Japanese Navy were in warship and aircraft production, and lacking in any definite plans for additional amphibious operations, production of the Type 3 Ka-Chi remained a very low priority.

Design

The Type 3 Ka-Chi was based a heavily modified version of the chassis of the army's Type 1 Chi-He medium tank, and thus featured considerably better armored protection and firepower than the earlier Type 2 Ka-Mi. It had smooth sides that faired into front and rear flotation pontoons made of sheet-metal. The front pontoon had a curved ' bow' shape and both pontoons could be jettisoned from inside the tank once the tank had landed. However, in practice, the pontoons were usually retained, as they provided some marginal additional protection against enemy fire. The undercarriage used the Hara system, with the addition of 2 more road-wheels and two more return rollers on each side than the Type 1 Chi-He. The hull was welded and water-proofed "with rubber seals and gaskets". The water propulsion was provided by twin-screws and it had two steering screws. The Type 3 Ka-Chi had a distinctive large snorkel behind the turret for aerating the

diesel engine The diesel engine, named after Rudolf Diesel, is an internal combustion engine in which ignition of the fuel is caused by the elevated temperature of the air in the cylinder due to mechanical compression; thus, the diesel engine is a so-ca ...

more efficiently and keeping the exhaust free of water. The main gun of Type 3 Ka-Chi was the Type 1 47 mm tank gun with barrel length of 2.250 meters (L/48), EL angle of fire by −15 to +20 degrees, AZ angle of fire of 20 degrees,

muzzle velocity Muzzle velocity is the speed of a projectile (bullet, pellet, slug, ball/ shots or shell) with respect to the muzzle at the moment it leaves the end of a gun's barrel (i.e. the muzzle). Firearm muzzle velocities range from approximatel ...

by 810 m/s and penetration of 55 mm/100 m, 40 mm/500 m, and 30 mm/1,000 m.Taki's Imperial Japanese Army: "Tank Guns"
/ref> This was the same 47 mm gun used on the army's Type 97 Shinhoto Chi-Ha. Secondary armament was a coaxial Type 97 heavy tank machine gun and a hull mounted weapon of the same type. The

gun turret A gun turret (or simply turret) is a mounting platform from which weapons can be fired that affords protection, visibility and ability to turn and aim. A modern gun turret is generally a rotatable weapon mount that houses the crew or mechani ...

was designed with an extended circular

cupola In architecture, a cupola () is a relatively small, most often dome-like, tall structure on top of a building. Often used to provide a lookout or to admit light and air, it usually crowns a larger roof or dome. The word derives, via Italian, fr ...

to keep the hatch above water. The vehicle required a crew of seven, one of whom (as with the Type 2 Ka-Mi) served as an on-board mechanic.

Service record

The Type 3 Ka-Chi was produced in very limited numbers, but proved useful due to its capability to be launched from a submarine, which enabled it to accommodate the increasingly difficult task of daytime reinforcement for isolated island garrisons located in the

South Pacific The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the continen ...

and in

Southeast Asia Southeast Asia, also spelled South East Asia and South-East Asia, and also known as Southeastern Asia, South-eastern Asia or SEA, is the geographical United Nations geoscheme for Asia#South-eastern Asia, south-eastern region of Asia, consistin ...

. The Type 3 Ka-Chi was deployed only in the Japan homeland and did not see combat.

Notes

References

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External links